Becker, Matthew R.
Tinker, Jeremy L.
Wechsler, Risa H.
AffiliationUniv Arizona, Dept Phys
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationThomas McClintock et al 2019 ApJ 872 53
Rights© 2019. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractExisting models for the dependence of the halo mass function on cosmological parameters will become a limiting source of systematic uncertainty for cluster cosmology in the near future. We present a halo mass function emulator and demonstrate improved accuracy relative to state-of-the-art analytic models. In this work, mass is defined using an overdensity criteria of 200 relative to the mean background density. Our emulator is constructed from the AEMULUS simulations, a suite of 40 N-body simulations with snapshots from z = 3 to z = 0. These simulations cover the flat wCDM parameter space allowed by recent cosmic microwave background, baryon acoustic oscillation and SNe Ia results, varying the parameters w, Omega(m), Omega(b), sigma(8), N-eff, n(s), and H-0. We validate our emulator using five realizations of seven different cosmologies, for a total of 35 test simulations. These test simulations were not used in constructing the emulator, and were run with fully independent initial conditions. We use our test simulations to characterize the modeling uncertainty of the emulator, and introduce a novel way of marginalizing over the associated systematic uncertainty. We confirm nonuniversality in our halo mass function emulator as a function of both cosmological parameters and redshift. Our emulator achieves better than 1% precision over much of the relevant parameter space, and we demonstrate that the systematic uncertainty in our emulator will remain a negligible source of error for cluster abundance studies through at least the LSST Year 1 data set.
VersionFinal published version
SponsorsDOE [DE-SC0015975]; Sloan Foundation [FG-2016-6443]; NSF [AST-1211889]; U.S. Department of Energy [DE-AC02-76SF00515]; Samuel P. Langley PITT PACC Postdoctoral Fellowship; Office of Science of the U.S. Department of Energy [DE-AC02-05CH11231]